Process for preparing voriconazole and starting materials and intermediates therefor

摘要

Optically pure voriconazole can be prepared in a high yield by a) subjecting 1-(2,4-difluorophenyl)-2(1H-1,2,4-triazol-1-yl)ethanone to Reformatsky-type coupling reaction with a substituted thiopyrimidine derivative to obtain a desired (2R,3S)/(2S,3R)-enantiomeric pair; b) removing the thiol derivative from the enantiomer to obtain racemic voriconazole; and c) isolating the racemic voriconazole by way of optical resolution using an optically active acid.